1. Field of the Invention
The present invention relates to switches and, more specifically, to vehicle steering column mounted switches for controlling vehicle operating circuits and components.
2. State of the Art
The evolution of steering column switches in motor vehicles has been toward greater integration of functions in a single switch lever. Previously, a plurality of individual switches, each controlling a single vehicle function, i.e., turnsignals, windshield wipers, headlights, etc., were mounted on the vehicle dashboard. Current steering column switch levers are designed to control a variety of functions for vehicle operating circuits or devices, such as turnsignals and hazard lights, high beam and low beam headlights with optional flash-to-pass, parking lights, fog lights, windshield wiper and wash functions, including multi-speed wipers with or without intermittent delay.
Typically, a steering column stalk switch includes a single lever or stalk pivotally mounted on one side of a housing attached to the vehicle steering column in an easily accessible position for access by the driver of the vehicle. The lever is gimballed at one end in housing so as to move in one and, typically, two mutually separate planes. Further, the lever may be provided with a rotatable end cap, and/or a slidable member movable along the longitudinal axis of the lever to control additional vehicle operating circuits. An intermediate member on the lever may also be rotatable to control another vehicle circuit or device. Actuators are mounted in the housing and, in response to movement of the lever in different directions or planes, rotation of the end cap, or movement of the slidable member, or rotation of the intermediate member on the lever, move a switching member carrying contacts between various switching positions to effect the switching of electrical connections for a particular vehicle operating circuit.
In some vehicles, particularly vehicles manufactured in Europe and/or Japan, two steering column stalk switches are provided, one mounted on the left side of the steering column and one on the right side of the steering column. The various vehicle operating circuits or devices described above are split between the two stalk switches, with the left stalk switch typically controlling vehicle headlight, parking light, fog light, flash-to-pass operating as well as turnsignal operations. The right mounted stalk lever typically controls windshield wiper, mist and wash devices.
However, regardless of whether one or two stalk switches are employed in a vehicle, vehicle design constraints require that the stalk switch lever and the housing assembly be as small as possible while at the same time provided easy access to and movement of the various switches on the stalk switch(es). At the same time, each stalk switch must meet further design constraints relating to a low manufacturing cost, a minimal number of individual components, ease of assembly, and ease of installation in the vehicle. Such stalk switches must also have the capability of easy modification to different vehicle design parameters, such as the ability to control when the vehicle fog lights are operable with respect to the state of the vehicle high beam or low beam headlights. It would also be desirable to provide a vehicle mounted steering column stalk switch which is capable of three modes or degrees of motion, namely, radially, axial and gear driven to operate a plurality of electrical circuits in the vehicle. It would also be desirable to provide a vehicle mounted steering column stalk switch which has the capability of operating a plurality of auxiliary circuits in a single stalk switch lever.
The present apparatus includes a housing mountable on a vehicle steering column. A lever is pivotal to the housing for pivotal movements about at least one axis between a center lever position and at least one other lever position. A carrier is mounted in the housing and responsive to movement of the lever. A detent surface is formed in one of the housing and the carrier, the detent surface including at least one detent, each detent associated with a respective other lever position. Conductive elements are mounted in the housing and are connectable to vehicle device operating circuits. At least one contactor is mounted in the carrier and selectively engages at least one of the conductive elements upon movement of the carrier between a center lever position at the at least one other lever position. Means for latching the carrier and the lever in the at least one other lever position is mounted on the carrier and engageable with the detent surface. A cancel pawl extends from the housing and is engageable with a rotatable member on the steering column. Returning means returns the carrier to the center lever position from engagement in the at least one other lever position upon pivotal movement of the cancel pawl. The returning means is biasingly mounted to permit sliding movement between the cancel pawl and the returning means when the lever holds the carrier in the at least one other lever position.
According to one aspect of the present invention, the at least one other lever position comprises two lever positions and the returning means includes a pair of cancel members mounted in the carrier and engageable by the cancel pawl upon pivotal movement of the cancel pawl to return the carrier to the center level position from one of the two lever positions, and the returning means includes means for biasing the cancel members to a normal position where force is not applied to the lever.
The present switch apparatus for actuating a plurality of electrical circuits affords several advantages over previously devised switch apparatus which forms a part of a vehicle stalk switch assembly. First, the actuator provides several switching functions thereby affording the ability to control several vehicle operating circuits and/or devices via a one piece member which is responsive to pivotal movement of the lever about two distinct axes. In this manner, a plurality of electrical circuits are controlled by the present switch apparatus which is constructed with a reduced number of separate components and electrical interfaces as compared to previously devices vehicle steering column switch apparatus. The leaf contact are insert molded into the grid member for further reduction in part count and electrical interfaces.